This
document can be downloaded as a PDF file! You must have the Adobe
Acrobat Reader to view it, though. Finally, an interesting
letter from Eugenio
Ragazzi in Italy about fake amber from China.

Fake
amber is not hard to make. It can be made from heating colored plastic,
using copal (not 'mature' amber) or other modern polymers. Amber that
looks 'too perfect' probably is! Quality specimens run into the thousands
of dollars.

It is
not particularly easy to identify fake amber from real amber. So,
how does one determine if you have a real sample of amber?

First,
one must understand that amber is the fossilized resin from ancient
trees. In the Dominican Republic, the tree is Hyemnaea (a leguminous
trees). Most modern legumes are smaller plants that have nodules in
the roots which contain bacteria that put nitrogen back into the soil;
peas, and clover are legumes. Modern day legume trees are common in
South America. In the Baltic area, millions of years ago, either pine
trees or eucalyptus (gum) trees probably produced the resin that turned
into amber.

Resin
from either of these types of trees, when placed in the proper conditions,
turns into amber. There is an intermediate stage where the resin might
look like amber, but is not changed enough (polymerized) to be considered
real amber. This 'young' resin is called copal. Copal is always much
younger than amber and has some characteristics which distinguish
it from real amber. For instance, copal is generally less dense than
amber.

Density
is measured in something called specific gravity. Regular amber often
has a specific gravity of 1.05 to 1.10 (where 1 is the same as water).
Copal looks similar, but has a lower specific gravity of 1.03 to 1.08.
A specific gravity of above 1.0 will cause the object to sink in fresh
water. While amber and copal will both sink in regular water, salt
water has a higher density. Amber and copal will both float in salt
water. Roughly 15 grams of salt in 100 mL of water (4 teaspoons of
salt to 8 ounces of water) will approximate salt water. In this solution,
both amber and copal should float. Copal is usually lighter than an
equal volume of amber. Unless you are very familiar with the weight
of amber, don't trust your estimate of the weight.

One fairly good way to determine fake amber is the 'hot point test'.
This is where the fine point of a very hot needle is put in the amber.
Real amber has a piney smell (or burnt resinous smell) and fake amber
can have an electrical, plastic or sweet smell to it. The problem
that you will have with this test is that most folks are not willing
to sacrifice their potential prize piece of amber to this test.

Equally
as bad is the burning test: amber burns with a black smoke, copal
will burn with a whitish smoke, plastic immations can also burn with
a black smoke. Again, who is willing to sacrifice their sample to
this rather harsh test?

Another
test is the acetone test. Acetone is the odoriferous chemical that
is used to remove nail polish. Copal is slightly soluble (hasn't hardened
enough over the millions of years) in acetone, so the surface will
get sticky. Regular amber is not soluble and therefore acetone should
not do anything to it. With plastic fakes, acetone can dissolve the
outer layer, which can sometimes be a shellac coating. This is probably
one of the easier tests.

Difficulty
does arise when the creator of fake amber will drill out the center
of the amber piece, insert a modern insect and then fill the hole
with hot copal. The resulting piece is very hard to distinguish from
the real thing. If the light is perfect, one may see the original
drilled hole, but don't count on it. Identification of an extinct
species of insect is difficult unless you are an expert entomologist!
'Old' and 'new' insects all look the same to the untrained eye.

For
the geologists, amber has a refractive index of 1.5 to 1.6 (copal
also is the same) while fakes of plastic and other chemicals will
give a very different refractive index. The refractive index is a
measure of how light is refracted when it goes
through the amber. In order to do this test, you need a refractometer
(a gemological instrument).

Amber
is fluorescent. That is, when ultraviolet light (UV) is directed on
the amber, it will fluoresce. Common fluorescent colors are yellow,
blue, green and orange. The intensity of the fluorescence can be different
with different types of amber. Dominican Republic amber usually fluoresces
blue. This is a simple test if you happen to have a black light. Just
shine the black light on the sample and observe the 'shine'.

Amber
is not hard, when using the Moh's scale. It ranks usually from 2 to
2.5. Your fingernail is about 2 and thus it is very difficult to scratch
amber. An American penny has a hardness of 3.0 and should scratch
amber. Steel wool, which has a hardness of 5.5, when scraped on amber
produces powder or very fine granules. If the piece is plastic, shavings
will likely result.

Raw
amber, when broken has conchoidal fracture. That mean is looks similar
to chipped glass. A chipped piece of glass will often show concentric
circles in the chipped area. That is conchodial fracture. Amber does
not have to chip in this fashion, but often will exhibit the type
fracture cut.

Lastly,
there are some pieces of amber in gem stores with 'spangles' in it.
This is attractive amber that has small disk shaped 'inclusions'.
The spangles are not natural. A few years ago I saw some Baltic amber
in a jewelry store. When I asked about the iridescent , sand dollar
shaped inclusions, I was told that this was a natural occurrence in
the amber. Wrong. This is made by heating amber in rapeseed oil. The
sun-spangles are thought to be from droplets of water which were trapped
in the amber. The droplets flatten and assume the spangle shape. Some
of the samples that I have seen are quite attractive! So, if you are
after a beautiful piece of amber, the spangles are great, but don't
be fooled into believing that they are a result of a natural occurrence.

Your
best bet is to purchase amber from a reputable source. A
page with some good pictures of fake
amber.